TWM450737U - Optical fiber assembly - Google Patents

Abstract

An optical fiber assembly includes a ferrule body with a plurality of optical fibers. An end face of each optical fiber extends past the front face of the ferrule body. A beam expanding element is generally adjacent the front face of the ferrule body and has a lens array aligned with the optical fibers. An index matched resilient medium engages the rearwardly facing surface of the beam expanding element and the end faces of the optical fibers.

Description

Fiber optic component Related application reference

The present application claims the priority of the prior U.S. Provisional Patent Application Serial No. 61/496,715, filed on Jun. 14, 2011, to the U.S. Patent. Incorporated herein.

New field

The present application relates to fiber optic assemblies, and in general to fiber optic ferrule assemblies, and more particularly to a multi-fiber ferrule assembly having an adjacent lens structure having a thermal expansion compensation structure.

New background

Systems for interconnecting multiple fibers typically employ multiple docking sleeve assemblies to facilitate operation and precise alignment of multiple fibers. The plurality of optical fibers are fixed in a casing body, and an end surface of each of the optical fibers is disposed substantially flush with or slightly protrudes from an end surface of the sleeve body to the end surface of the sleeve body. The end surfaces or end faces of the plurality of fibers are typically polished to the desired finish. When the complementary plurality of sleeve assemblies are docked, each of the fibers in one of the sleeve assemblies is aligned with a mating fiber of the other sleeve assembly.

In some applications, the end faces of the plurality of butted fibers are in physical contact with one another to achieve the purpose of transmitting signals between pairs of docking fibers. In these applications, various factors are likely to reduce the light between the paired fibers that are docked. Transmission efficiency, such as irregularities in the end faces of the fibers, burrs or scratches, misalignment of the fibers, and the presence of dust or debris at the mating interface between the fibers.

Since the optical path is small relative to the size of any foreign matter such as dust or debris, any of these impurities may interfere with the transmission of light. The extended beam connector expands the width of the beam and causes the beam to travel across the air gap between the connectors. By expanding the beam, the relative size difference between the dust or debris and the beam is increased, which thereby reduces any dust or debris and any misalignment on the light transmission efficiency. Therefore, extended beam fiber optic connectors are typically used in unclean environments and high vibration environments.

The extended beam connector includes a lens mounted adjacent to an end face of each of the fibers. There are two types of commonly used lenses: collimating lenses and cross-focusing lenses. The collimating lens receives light from the fiber and expands the beam to a relatively large diameter. When a collimating lens is employed, a second lens and sleeve assembly is similarly provided with a lens for receiving the expanded beam adjacent the end face of the second fiber and for refocusing the beam at the end face of the second fiber. The cross-focusing lens receives light from the fiber, spreads the light to a relatively large diameter, and then focuses the relatively large diameter of light at a particular focus. For a cross-focusing lens, the lens and cannula assembly can interface with another lens and cannula assembly having a cross-focusing lens, or with a lensless cannula assembly known in the art.

In one design, a plurality of fibers of an extended beam multi-fiber ferrule assembly extend through the ferrule body and are in contact with a fiber optic lens plate or fiber optic lens element. The quality of contact between the fiber and the lens plate is one of the factors that affect the performance of the bushing assembly. The fiber can be made of a material different from the sleeve body and the lens group Material formation. The difference in thermal expansion coefficients of the plurality of components may result in inconsistent contact between the optical fiber and the lens plate. The inconsistent contact may result in a decrease in the optical transmission quality of the cannula assembly. Accordingly, it is desirable to provide a multi-fiber lensed cannula assembly that compensates for differences in thermal expansion between various components in the component.

New summary

In one aspect, a fiber optic assembly includes a plurality of substantially parallel fibers, a sleeve body, a beam expanding element, and an index matching medium. Each fiber has an end face and is located within the casing body. The sleeve body has a front surface with end faces of the respective fibers located substantially adjacent and extending through the front surface of the sleeve body. The beam expanding element is substantially adjacent the front surface of the sleeve body, the beam expanding element having an array of lenses and a rearward facing surface. The lens array is aligned with the plurality of fibers and spaced apart from the plurality of fibers by a predetermined distance. The index matching elastic medium engages the rearward facing surface of the beam expanding element and the end faces of the plurality of optical fibers.

In another aspect, a fiber optic assembly includes a plurality of substantially parallel fibers, each fiber having a fiber index of refraction and an end face. The end faces of the plurality of fibers are substantially aligned on a common plane. A sleeve body has the plurality of fibers positioned therein, the sleeve body having a front surface. A beam expanding element is substantially adjacent the front surface of the sleeve body. The beam expanding element has a beam expanding element refractive index and a lens array aligned with the plurality of fibers of the sleeve body. Lens array Intersected with the plurality of fibers by a predetermined distance. An elastic medium engages the end faces of the plurality of optical fibers and the beam expanding element, and has an elastic medium refractive index. The fiber refractive index, the beam expanding element refractive index, and the elastic medium refractive index are approximately equal.

In still another aspect, a fiber optic assembly includes a plurality of substantially parallel fibers, each fiber having an end face. A sleeve body positions the plurality of fibers therein, the sleeve body including a front surface. The end faces of the respective fibers are located substantially adjacent the front surface of the sleeve body and extend through the front surface of the sleeve body. A beam expanding element is substantially adjacent the front surface of the sleeve body, the beam expanding element having a front surface and a back surface. The front surface is provided with a lens array aligned with the plurality of fibers of the sleeve body, the lens array being spaced apart from the plurality of fibers by a predetermined distance. The rear surface of the beam expanding element is located substantially adjacent the front surface of the sleeve body. The rear surface of the beam expanding element has a recess extending toward the front surface of the beam expanding element, the recess having a rearward facing surface. An elastic medium is disposed within the recess, the elastic medium engaging the rearward facing surface of the beam expanding element and an end surface of the plurality of optical fibers.

Simple illustration

The organization and operation of the present application and its further objects and advantages are best understood by referring to the following detailed description in conjunction with the accompanying drawings in which Medium: Figure 1 is a perspective view of an embodiment of a connected cannula assembly Figure 2 is a partially exploded perspective view of the assembly-fixing device of the bushing assembly of Figure 1; Figure 3 is a perspective view similar to Figure 2 but viewed from the rear; Figure 4 is substantially along the 4-4 of Figure 1. A cross-sectional view made by the line; and Fig. 5 is an enlarged view of the circled portion of Fig. 4.

detailed description

While the present invention is susceptible to various embodiments of the embodiments of the present invention, it is understood that It is not intended to limit the application to the drawings shown herein.

Likewise, a reference to a feature or aspect is intended to describe a feature or aspect of an example of the application, and does not imply that each embodiment must have the described feature or aspect. Moreover, it should be noted that the specification shows a number of features. While certain features have been combined to illustrate potential system designs, these features may also employ other combinations that are not explicitly disclosed. Therefore, the combinations are not intended to be limiting unless otherwise stated.

In the illustrated embodiment, the directional representations, ie, up, down, left, right, front and back, etc., are not absolute, but are relative, to explain the structure and motion of the various components in this application. These representations are appropriate when the components are in the position shown in the figures. However, if the description of the location of the component changes, then these representations are considered to change accordingly.

Referring to Figure 1, a multi-fiber MT type lensed sleeve is shown. Component 10. The cannula assembly 10 includes a cannula body 11 having a plurality of optical fibers 51 of a plurality of optical cables 50 positioned therein. A light or beam expanding element, such as lens plate 30, is mounted to the sleeve body 11. As shown, the cannula assembly 10 includes a row of fibers 51 having twelve fibers, but if desired, the cannula assembly can be configured to receive more or fewer fibers.

The sleeve body 11 is substantially rectangular and has a substantially flat front surface 12 and a substantially flat rear surface 13. As shown in FIG. 2, the sleeve body 11 includes a row of twelve substantially cylindrical fiber receiving apertures 15 extending through the sleeve body 11 to the front surface 12. Additionally, the sleeve body 11 can include a pair of alignment holes or alignment sockets 16 on opposite sides of the array of fiber receiving apertures 15. The alignment aperture 16 is substantially cylindrical and extends between the front surface 12 and the rear surface 13. In certain embodiments, the apertures 16 may not extend all the way to the rear surface 13, may not have a uniform cross-section (such as the illustrated cylinder), but may be tapered as disclosed in US Pat. No. 7,527,436. Or stepped or may have a uniform non-circular cross section (such as a hexagonal cross section). The registration apertures 16 are configured to receive a rod (not shown) therein for facilitating alignment when a pair of components are docked. In the illustrated MT sleeve body 11, each of the alignment holes 16 has a diameter of about 700 microns. Other diameters may be used for the alignment holes 16 if desired.

The sleeve body 11 may be formed of a resin capable of injection molding such as polyphenylene sulfide or polyether quinone, and may include an auxiliary agent such as cerium oxide (SiO ₂ ) to increase the strength and stability of the resin. . Other materials can be used if desired. One of the optical fibers 51 of the multi-cable 50 is located in each of the optical fiber receiving holes 15 and extends through the front surface 12 of the sleeve body 11. The end face 52 of the optical fiber 51 can extend through the front surface 12 of the cannula body 11 for a distance of 3-4 microns or more (such as 20 microns). In some applications, the end face 52 may extend through the front surface 12 of the cannula body 11 up to 50 microns. For the sake of clarity, the distance that the end face 52 extends through the front surface 12 of the cannula body 11 is exaggerated in Figures 4 and 5. In one example, the fiber 51 can have a diameter of about 125 microns. The optical fiber 51 can be fixed in the fiber receiving hole 15 by an adhesive such as an epoxy resin. The end face 52 of the fiber 51 adjacent the front surface 12 can be polished or otherwise machined to the desired finish.

The lens plate 30 is substantially rectangular and has a front surface 32 and a rear surface 33. The lens plate 30 may be formed of an optical grade resin capable of injection molding having a refractive index closely matching the refractive index of the optical fiber 50. In other words, the optical fiber 51 has a fiber refractive index and the lens plate 30 has a lens plate refractive index. It is desirable to select the material such that the refractive index of the fiber and the refractive index of the lens plate are approximately equal.

A recess 34 is located at the center of the front surface 32 and includes a plurality of lens elements 35 of a lens array. A lens element 35 is aligned with an optical fiber 51 located in the respective fiber receiving opening 15 of the sleeve body 11. In an extended beam connector, two common types of lens elements are the collimation type and the cross focus type. In the illustrated embodiment, the lens element 35 is of the cross-focus type and includes a convex shape (Fig. 5) that protrudes from the bottom portion 34' of the recess 34 toward the front surface 32 of the lens plate 30. The rear surface 33 of the lens plate 30 has a substantially rectangular socket or recess 36 therein. The recess 36 is substantially aligned with the array of lens elements 35, and thus the recess 36 is aligned with the respective fibers 51 when the lens plate 30 is secured to the cannula body 11. The recess 36 has a rearward facing surface 37 that is substantially parallel to the rear surface 33 of the lens plate 30 and The rear surface 33 of the lens plate 30 is spaced forward by a distance. The depth of the recess 36 defines the distance between the rearward facing surface 37 and the rear surface 33.

The lens plate 30 also includes a pair of cylindrical guide holes or guide sockets 38 that are disposed to align with the alignment holes 16 of the cannula body 11. Each of the guide holes 38 may be provided to have a diameter matching the diameter of the alignment hole 16 of the sleeve body 11 or a diameter larger than the diameter of the alignment hole 16 of the sleeve body 11. The lens plate 30 can have a pair of circular shims or pedestals 40 that protrude from the rear surface 33 while surrounding each of the guide holes 38. The length of the shim 40 can be selected to define a uniform and predetermined distance or gap between the front surface 12 of the cannula body 11 and the rear surface 33 of the lens plate 30.

A resilient index matching medium or insert 45 has a front end face 46 and a rear end face 47 and is located within the recess 36 of the lens plate 30. The front end face 46 is pressed against the rearward facing surface 37 (Fig. 5) of the recess 36. The rear end face 47 is pressed against the end face 52 of the optical fiber 51. Depending on the distance the fiber 51 extends through the front surface 12 and the thickness and other characteristics of the resilient insert 45, the rear end surface 47 can also be pressed against the front surface 12 of the sleeve body 11. Thus, when the lens plate 30 is fixed to the sleeve body 11, the elastic insert 45 is substantially aligned with the lens elements 35 of the array and the respective optical fibers 51 and is pressed between the lens elements 35 of the array and the respective optical fibers 51. The elastic insert 45 is shown as being substantially rectangular to match the shape of the recess 36. If desired, the recess 36 and the resilient insert 45 can have other shapes and in any case may not have a matching shape.

Although the elastic insert 45 shown in Figures 2-5 is relatively thick for illustrative purposes, the elastic insert 45 can have various thicknesses. More specifically, the depth of the recess 36 and the thickness of the elastic insert 45 can be selected as needed. As long as the elasticity of the elastic insert 45 compensates for the difference in thermal expansion between the sleeve body 11 and the lens plate 30 with respect to the optical fiber 51. As an example, if the sleeve body 11 and the lens plate 30 are formed of a certain type of polymer and the optical fibers are formed of a glass material such as ceria, these components of the cannula assembly 10 may have different coefficients of thermal expansion. As the temperature of the operating environment of the cannula assembly 10 changes, the relative difference in thermal expansion between the plurality of fibers 51 and other components of the component can be up to about 3-4 microns. It is confirmed that the elastic insert 45 of at least 100 micrometers thick in one embodiment and the elastic insert 45 of at least 75 micrometers thick in another embodiment compensates for this difference in thermal expansion. Depending on the performance characteristics of the elastic insert 45, the elastic insert 45 can take on other thicknesses.

The elastic insert 45 may be formed of an elastic material having a refractive index approximately equal to the refractive index of the lens plate 30 and the optical fiber 51. In other words, the fiber refractive index, the lens plate refractive index, and the elastic insert refractive index are expected to be approximately equal. By selecting on the material such that the refractive indices are approximately equal, the transmission loss due to the difference between the refractive indices is minimized. In one example, the elastic insert 45 can be formed from silicone, but in some applications other materials such as urethane can also be employed.

Referring to Figures 2 and 3, the process of mounting the lens plate 30 on the cannula body 11 is illustrated. The sleeve body 11 is shown as a plurality of optical fibers 51 having a plurality of optical cables 50 fixed in a plurality of optical fiber receiving holes 15, respectively. The length of each of the optical fibers 51 extends beyond the front surface 12 of the sleeve body 11, but is substantially smaller than the lengths shown in Figures 4 and 5. The end face 52 of the optical fiber 51 can be polished as desired or otherwise processed for smoothness. The lens plate 30 is spaced apart from the sleeve body 11 by a certain distance At the same time, the guide holes 38 of the lens plate 30 are aligned with the alignment holes 16 of the front surface 12 of the sleeve body 11. The elastic insert 45 is shown in FIG. 2 and FIG. 3 as a separate component for assembly between the sleeve body 11 and the lens plate 30. In some cases, the elastic insert 45 can be inserted into the lens plate 30 as part of a pre-assembly process to simplify the production process.

An assembly fixture 60 can be used to align the sleeve body 11 with the lens plate 30. More specifically, the fixture 60 has a substantially rectangular body 61 and a pair of spaced apart guide posts 62 that pass through the guide holes 38 of the lens plate 30 and into the sleeve body during production. The alignment hole 16 of the 11 is aligned to align the sleeve body with the lens plate. Each of the guide posts 62 can include an enlarged first portion 63 adjacent the body 61, the first portion 63 being diametrically shaped to substantially match the diameter of the guide aperture 38 of the lens plate 30. Each of the guide posts may further include a second portion 64 spaced apart from the body 61, the second portion 64 being diametrically shaped to substantially match the diameter of the alignment aperture 16 of the sleeve body 11 and less than the diameter of the first portion 63. .

During assembly, the lens plate 30, along with the resilient insert 45 located in the recess 36, slides onto the guide post 62 of the fixture 60 while the end of the guide post extends through the guide aperture 38 and through the rear surface 33 of the lens plate 30. . The adhesive 42 can be applied to the rear surface 33 of the lens plate 30, and the guide post 62 slides into the alignment hole 16 of the front surface 12 of the sleeve body 11. The lens plate 30 and the elastic insert 45 are relatively moved toward the sleeve body 11 having the optical fiber 51 fixed therein. When the lens plate 30 reaches the sleeve body 11, the end face 52 of the optical fiber 51 will engage and compress the elastic insert 45. When the adhesive is cured or hardened, the lens plate 30 and the elastic insert 45 are fixed against the sleeve body 11 and the optical fiber 51, respectively.

While a preferred embodiment of the present invention has been shown and described, it will be understood that various modifications can be made by those skilled in the art without departing from the scope of the invention and the scope of the appended claims. .

10‧‧‧ casing assembly

11‧‧‧ casing body

12, 32‧‧‧ front surface

13, 33‧‧‧ rear surface

15‧‧‧Fiber receiving hole

16‧‧‧ alignment hole or alignment socket

30‧‧‧ lens plate

34‧‧‧ recess

34’‧‧‧ bottom

35‧‧‧ lens elements

36‧‧‧ recess

37‧‧‧ surface

38‧‧‧Guide or guide socket

40‧‧‧shims or pedestals

45‧‧‧Flexible plugin

46‧‧‧ front end

47‧‧‧ rear end face

50‧‧‧Multiple cable

51‧‧‧ fiber optic

52‧‧‧ end face

60‧‧‧Fixed devices

61‧‧‧Ontology

62‧‧‧Guide column

63‧‧‧ first

64‧‧‧ second

Figure 1 is a perspective view of an embodiment of a connected cannula assembly; Figure 2 is an exploded perspective view of a portion of the cannula assembly of Figure 1 in an assembled assembly; Figure 3 is similar to Figure 2 but from the rear A perspective view of the view; FIG. 4 is a cross-sectional view taken substantially along line 4-4 of FIG. 1; and FIG. 5 is an enlarged view of the circled portion of FIG.

10‧‧‧ casing assembly

11‧‧‧ casing body

12, 32‧‧‧ front surface

13‧‧‧Back surface

30‧‧‧ lens plate

34‧‧‧ recess

35‧‧‧ lens elements

38‧‧‧Guide or guide socket

50‧‧‧Multiple cable

51‧‧‧ fiber optic

Claims (20)

A fiber optic assembly comprising: a plurality of optical fibers, substantially parallel and each of the optical fibers having an end surface; a sleeve body having the plurality of optical fibers disposed therein, the sleeve body having a front surface, end faces of the respective optical fibers Located proximate to and extending through the front surface of the sleeve body; a beam expanding element substantially adjacent the front surface of the sleeve body, the beam expanding element having an array of lenses and a rearward facing a surface, said lens array being aligned with said plurality of fibers and spaced apart from said plurality of fibers by a predetermined distance; and an exponentially matched elastic medium engaging said said beam expanding element a rearward facing surface and an end face of the plurality of optical fibers. The fiber optic assembly of claim 1, wherein the rearward facing surface of the beam expanding element is located substantially adjacent the front surface of the sleeve body but with the sleeve body The front surface is spaced apart by a distance and the beam expanding element has a recess extending toward the lens array, the elastic medium being located within the recess. The fiber optic assembly of claim 2, wherein the rearward facing surface is located in the recess, and a front end surface of the elastic medium is pressed against the rearward facing surface of the recess A rear end surface of the elastic medium is pressed against the end faces of the respective optical fibers. The fiber optic assembly of claim 1, wherein the The elastic medium is formed of a resin material. The fiber optic assembly of claim 1, wherein the end faces of the plurality of fibers are substantially aligned on a common plane. The fiber optic assembly of claim 1, wherein the plurality of fibers, the beam expanding element, and the elastic medium each have a refractive index and each refractive index is approximately equal. The fiber optic assembly of claim 1, wherein the beam expanding element is a substantially rectangular lens plate having a plurality of lenses, each lens being aligned with one of the plurality of fibers . The fiber optic assembly of claim 1, wherein the plurality of fibers are arranged in at least one substantially linear array. The fiber optic assembly of claim 1, wherein the elastic medium is at least about 75 microns thick. A fiber optic assembly comprising: a plurality of optical fibers, substantially parallel, each optical fiber having a refractive index of a fiber and an end face, the end faces of the plurality of optical fibers being substantially aligned on a common plane; a casing body to make the plurality The root fiber is located therein, the sleeve body has a front surface; a beam expanding element substantially adjacent to the front surface of the sleeve body, the beam expanding element having a beam expanding element refractive index and An array of lenses aligned with the plurality of fibers of the sleeve, the lens array being spaced apart from the plurality of fibers by a predetermined distance; and an elastic medium joining the end faces of the plurality of fibers and the light The beam expanding element, and having an elastic medium refractive index; wherein the fiber refractive index, the beam expanding element refractive index, and the elastic medium refractive index are approximately equal. The fiber optic assembly of claim 10, wherein one of the sleeve body and the beam expanding element has a recess in which the elastic medium is located. The fiber optic assembly of claim 10, wherein the beam expanding element has a recess, and wherein the elastic medium is located in the recess, the recess includes a rearward facing surface, and the elastic medium A front end face is pressed against the rearward facing surface of the recess and a rear end face of the elastic medium is pressed against the end faces of the respective optical fibers. The fiber optic assembly of claim 10, wherein the plurality of fibers deform the elastic medium. The optical fiber component of claim 10, wherein the elastic medium is formed of a resin material. The fiber optic assembly of claim 10, wherein the elastic medium is at least about 75 microns thick. The fiber optic assembly of claim 10, wherein the beam expanding element is a substantially rectangular lens plate, the lens plate having a plurality of lenses, each lens being aligned with one of the plurality of fibers . The fiber optic assembly of claim 10, wherein the plurality of fibers are arranged in at least one substantially linear array and the elastic medium extends along a linear array of the plurality of fibers. A fiber optic assembly comprising: a plurality of optical fibers, substantially parallel and each of the optical fibers having an end surface; a sleeve body having the plurality of optical fibers disposed therein, the sleeve body having a front surface, end faces of the respective optical fibers Located proximate the front surface of the sleeve body and extending through the front surface of the sleeve body; a beam expanding element substantially adjacent the front surface of the sleeve body, the beam expanding The element has a front surface and a rear surface, the front surface being provided with a lens array aligned with the plurality of fibers of the sleeve, the lens array being spaced apart from the plurality of fibers by a predetermined distance, The rear surface of the beam expanding element is located substantially adjacent the front surface of the sleeve body, the rear surface of the beam expanding element having a recess extending toward the front surface of the beam expanding element, The recess has a rearward facing surface; and an elastic medium located within the recess, the resilient medium engaging the rearward facing surface of the beam expander element and The end faces of optical fibers. The fiber optic assembly of claim 18, wherein the plurality of fibers, the beam expanding element, and the elastic medium each have a refractive index and each refractive index is approximately equal. The fiber optic assembly of claim 18, wherein the elastomeric medium is at least about 75 microns thick.